


Alternate Uses for Bathtubs

by espadachina



Category: Avatar: The Last Airbender
Genre: Alternate Universe - Zuko is a Merman, F/M, Katara Introduces the Concept of Waffles, Shenanigans, Wheelbarrows are Useful, Zutara
Language: English
Status: Completed
Published: 2016-01-12
Updated: 2016-01-22
Packaged: 2018-05-13 08:31:25
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 6
Words: 5,715
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5701849
Author URL: https://archiveofourown.org/users/espadachina/pseuds/espadachina
Summary: <blockquote class="userstuff">
              <p>Katara finds a big fish and takes him home.</p>
            </blockquote>





	1. Flotsam

**Author's Note:**

> There are so many AUs with Katara being a mermaid. So I wrote Zuko as a merman.

The backs of the waves glisten with silver, frothing into white lace as they tumble over themselves and against the sand, which crunches softly under her bare toes. The water beckons her, pulls at her feet, making soft, calming _shhhh_ noises. She is alone.

She inhales the salty scent of the ocean, lets it flow through her and fill her lungs, fill her. Her hair whips around her head, wild and free.

The smooth curve of beach is interrupted by a dark shape. Katara falters, suspicious, curious. Then she runs.

It is a man. Sideways in the sand, curled into a kind of fetal position. The lower half of his body is that of a fish. Katara's heart leaps into her throat. A merman.

A stab of fear. Merpeople were evil. They lured sailors into their watery clutches, beguiling them with siren songs and their sinister beauty. They called up storms to wrack the port towns, flood the fields, and swallow swimming children. They lived among the sea-beasts, enticing them to rage against fishermens’ boats, biting through nets and lines. Children weren't allowed out of sight when on the beach, and boats always had a cache of arrows and harpoons. Dangerous creatures, merpeople.

Her initial terror subsides into bemusement. This man is no threat to her. In fact, she doesn't know if he's even alive. Glancing around, furtively, she squats down beside him and observes.

He is young. His skin and hair, still strangely wet, gleam mercurial. His face is strong and sharp, marred only by what appears to be a... burn scar... over the left half of his face. Katara grimaces. It probably came from human hands, that scar. Katara notices that his gills are moving gently.

Katara jumps back, cautious. Merpeople had adapted a strange breathing system that worked both above and below water. Submerged, they worked like any fish's gills, pumping seawater through them to collect oxygen. Above water, it seemed they filled their gills with enough water to be able to breathe a while, and it was assumed that their strange skin also allowed them to absorb oxygen from the air as well. _Like a frog's_ , thought Katara. _But frogskin has to remain wet._

An idea took root in her mind. _Ridiculous_ , she tells herself. _I should leave him here to die_.

_Save him_ , whispers her heart.

"Hey," she croaks, awkwardly. She pokes him on the shoulder, wary lest he leap up and bite her with his needle-teeth. His entire body shivers at the touch. "Uh... merman. Do you need help?" She goggles at the strangeness of the situation.

The merman winces, his gills flaring. Katara scrambles back as he gathers himself, pushes himself up, visible strain shuddering through his muscles. His eyes meet Katara's and they are gold.

It is such a shock after the silver of night that Katara forgets to breathe. No one told her merpeople had eyes like that.

The merman bares his teeth at her and hisses, weakly. His teeth look like hers. Katara is relieved. "You stop that," she tells him sternly, grasping at the strands of her courage. He is weak and out of his element, literally. "I asked you a question."

The merman's eyes flash with anger, irritation, before shifting to surprise. He looks momentarily like a confused puppy, and Katara has to bite back a smile. He then decides to ignore her, his eyes strain towards the sea, and his body follows. As his fish-tail bends, he gives out a noise of pain. Katara takes a closer look and sees that the tail fin is in shreds. Her feet smart at the sight. He appears enraged at the sight of himself, and clenches his fist.

"That doesn't look good," Katara comments.

"How perceptive," the merman spits out, glaring. There is anger and distrust and pain and arrogance in his voice. Affronted, Katara gets up, brushing her legs off matter-of-factly.

"I assume you don't want my help, then," she replies coolly. She spins and starts to leave.

"Wait." She turns and sees the merman hunched over, seemingly mulling over his options. Then his head turns to look at her. Katara can't get used to his eyes, their angry gold. "You’re just a human," he continues, possibly to himself. Katara seethes. "I'll die if I stay here, and I'll die if I go back. What can you do?" He asks it scathingly, not expecting any helpful response.

"Well," Katara muses. "We could always put you in the bathtub."


	2. Jigsaw Fins

**Summary for the Chapter:**

> Now that there's a merman in her bathtub, Katara manages to avoid his sass in favor of keeping him alive.

**Notes for the Chapter:**

> I love snarky Zuko/Katara interactions, and Mer!Zuko's pretty pissed rn, so there's quite a bit of it.

After having explained to an irate merman what a bathtub was, Katara practically flew back home to find a wheelbarrow. Her father loved puttering around in the garden; there was one in the shed. She had carefully removed said wheelbarrow from the shed, leery of the squeaky hinges. It was difficult to push through the sand, but she managed.

"You're back," the merman mutters when she arrives, panting. He seems resigned and shocked, but he hides the latter feeling well. Katara pushes the wheelbarrow into the ocean until water sloshes into it. She struggles against the tide and tugs it next to the merman, where she plops down heavily. He eyes her distrustfully.

"You want me to get in there?"

"Well, I don't think I can carry you."

“Ugh.” His distaste is obvious.

Somehow they manage to get him up and into the wheelbarrow, him dragging with his arms and she pushing up his thick tail. The weirdness gets to her and she laughs silently, her giddiness unfazed by the sharp looks the merman throws her. His tail feels like any fish’s, slick and smooth, but oh-so-much bigger and oh-so-much heavier.

It is uncomfortable, but he fits, more or less.

Katara pushes the wheelbarrow across the beach. It is heavy, filled to the brim with ocean and incensed merman. He growls when water slops out, hisses when the wheelbarrow bumps, mutters to himself when she stops and rests. The stars twinkle in the sky, and the moon watches, bemused.

Once they reach her house, Katara pauses. She hadn’t thought much farther than this, and was now contemplating how to get the merman up the stairs and into her house. “Um,” she says.

“What is it now?” he mutters, suspicious.

“Wait here,” she tells him, and unlocks the door. She sprints upstairs and yanks the blanket off of her bed, her mind already working feverishly on the story she would tell her grandmother the next morning. _I took a walk at night and dipped my feet in the water, but only in the really shallow parts, of course, and when I got back I was so tired I just plopped into bed. That’s why the blankets are salty and smell of fish._

“What is that?” the merman asks when she returns, eyeing the big white blankets in puzzled anger. A frown creased his forehead and drew one eyebrow down. Perhaps he is always angry.

“This, your highness, is a blanket, commonly used to cover the bodies of sleeping humans. Right now, however, they are to be your mode of transportation to the bathtub.” She spreads the blanket out over the stairs leading to the door. “I’m going to tip you out onto it and then pull you up, okay?”

“How undignified,” he snorts. But at this point, he has no other options. So she tips him onto the blanket, and the roses taste salt for days.

“Try to weigh less,” Katara instructs in a whisper as she pulls him up the stairs.

“Right. I will, thanks for the tip,” is the sarcastic reply.

In the end, Katara manages to pull him not only up the front porch, but also up the stairs leading to her bathroom. She asks for his help in not making any loud noises, and he obliges, pushing himself up with his arms and keeping his tail straight.

“That’s a bathtub?” he hisses when he sees it, all scorn and indignation. “That’s barely bigger than that wheelbarrow!” He was learning fast. Katara was proud, and ignored him.

“Oh.” A thought came to mind. “Is normal water okay? I mean, not salt water, just plain water, without the salt?” she asks quietly. He glares at her from the bathroom floor.

“I’ll manage.” He hoists himself into the tub. Katara is struck by the absurdity. A merman in her bathtub.

Katara shows him how to handle the knobs that control the flow of hot and cold water. The merman is deeply fascinated by this, and alternates between going wide-eyed at the sensation of such warm water and frowning at the sputter of cold. In the light, his scales shine a brick red, the very edges tipped in black, the fins running down his hips and sprouting from the end of his tail blurring into the gold of his eyes. His hair is either black or dark brown; as it is perpetually wet, Katara can’t be sure.

As he plays with the hot and cold water, Katara attempts to do something about the tail problem. There really isn’t much she can do, it being wet and slippery. She leaves him momentarily to grab a needle and thread. Perhaps she can piece together what’s left of it.

He eyes her warily as she approaches him and sits on a white porcelain chair. “What are you doing?” he asks coldly.

“I’m going to stitch up your tail,” she responds curtly. “It might hurt.”

He uncoils his tail from under him. “But it’ll help?” He is completely vulnerable, and hates it. But this girl is offering to help him, fix him, and he’s going to take everything she gives to him.

“Probably.” He nods tightly and fans out the tattered remains of his tail.

The skin twitches when she touches it. She clamps the tail down under her left arm, threads the needle, and sets to work. The quiet hisses of the merman against the splashing of the water accompany her hands as they carefully pull, untwist, and piece together the jigsaw puzzle of his fins. The muscles jerk against her forearm whenever she stabs through the skin, and the merman’s knuckles turn white where he clings to the edge of the tub.

When she is finished, his tail is far from perfect. Stitches run across the fins in a web of black crosshatches, giving it a Frankenstein’s-monster kind of look. As soon as her arm lifts, he snatches his tail back and runs his fingers over it.

She explains the plug in the drain and he nods, not looking up. She leaves him with the words, “Don’t flood my bathroom.”

She goes to her room and lies on her carpet. _What have I done?_


	3. Morning Concepts

**Summary for the Chapter:**

> Katara wakes up and there is still a fish in her bathtub.

**Notes for the Chapter:**

> They still don't know each other's names asdfhugifk

When she wakes up to the squawk of her alarm early the next morning, she is confused to find the ceiling farther away than it usually is. As she sits up groggily, the night comes rushing back to her. She jumps to her feet and hop-sneaks to her bathroom, presses her ear against the door, and tries to ignore her beating heart. _Is he in there?_

She pushes open the door slowly. Silence. Her head peeks in.

There is water on the floor. Not the flood she had expected, but still enough to cause irritation. More importantly, however, there is still a merman curled up in her bathtub. Asleep. With his head under water.

Katara swallows the initial terror at seeing what looks like a drowned human boy and looks in the mirror. Her hair is a mess. Her habit of leaving her hair down on her occasional walks always leaves her with tangles. With practiced diligence she combs through her hair with her fingers. She realizes she can’t take a shower with the merman in her bathtub. _Wonder how I’ll explain that to Gran Gran,_ she thinks.

A French braid will be enough to hold her hair for today. She decides to sneak a shower later.

She turns on the tap and washes her face. The gurgle of the water as it swirls down the drain rouses the merman, who squints at his tail, his surroundings, before finally directing his judgmental stare at her.

“What happened to your hair?”

Katara did not like his disgusted tone. “I don’t know about mermaids,” she began, “but humans get knots in their hair when they go around rescuing injured merpeople at night. This is a French braid, and it keeps hair out of my face and tangle free, mostly.”

“It looks ridiculous,” was his scathing response.

“Excuse me.” Katara turned around to glare at him. “You might want to be nicer to your rescuer and only source of food.”

“Of course,” he replies immediately, his fins flaring. “I can only describe it as the _epitome_ of beauty.” His attitude begs to differ, and Katara narrows her eyes at him.

“It’s 7 in the morning. I don’t need your sass,” she snaps at him. He glares at her.

“What do you mean, 7 in the morning?”

“Oh.” Katara realizes that mermaids might not tell time with numbers. “Uh... well, we humans tell time... I mean, we assign numbers to certain parts of the day. Like, when the sun is directly overhead, it’s 12 o’ clock. After that it’s 13 o’ clock and so on until 24 o’ clock, which is when the night starts turning into day... and then it goes from 1 o’ clock to 2 o’ clock and so on...”

“How strange,” he muses, interested and superior. “What is a clock?”

“A device we use to tell what time it is.” She holds out her wrist to him, showing him her watch. “See the black stick things?  The small one points to what hour it is – 7 o’ clock. The big one points at the number of minutes after exactly 7 o’ clock. It’s 7:08, so the big stick points at the 8.”

The merman shifts in his tub – Katara wonders at how quickly it became _his_ – and leans forward to stare at the watch. There is silence for a few seconds, then he looks up. His eyes fulminate. “I don’t get it,” he growls.

“That’s okay,” she replies, feeling a strange urge to pat his head. “The point is that it’s early.”

He just looks at her.

“I’m going to get breakfast. Food,” she adds when she catches his uncomprehending stare. “I’ll try and bring you some.”

“You’d better.” He sulks. Katara chews on her lips to keep from smiling.

The carpeted stairs muffle her footsteps as Katara flies down the stairs into the kitchen. Her grandmother's diet isn't exactly the most varied, but there are enough ingredients to pull together a decent breakfast. 

Well. Decent enough for her. It'll have to do for the merman as well.

“Do merpeople eat waffles?” Katara wants to know as she re-enters the bathroom. The merman is alert, following her with his eyes as she sits on what she’d just explained was a _toilet,_ function as of yet unknown. There is a tower of flat, circular, pale yellow steaming things on a plate.

“I’ve never had a waffle.” Katara feels laughter bursting up inside her and chokes. The way he said it made it seem as though waffles were some strange, foreign object to him. And they were.

“Prepare to have your mind blown,” she tells him, drizzling them with maple syrup.

In retrospect, it was not a good idea to feed the merman waffles. He immediately demanded more, astounded by the taste of sweetness and the addicting crunch between his teeth. He devoured them, dripping syrup into the bathtub and onto the floor. Katara rolled her eyes and obligingly left to make more.

When his stomach was finally distended to interesting proportions and he had stopped beg-ordering her to pass him another waffle, Katara brushed her teeth, which was another thing the merman took interest in. She let him try some of the toothpaste, which he spit out in disgust. While she went through her daily morning hygiene rituals, he pulled the plug. And watched in amazement as water swirled down the drain.

“Impreshed?” Katara asked through a mouth full of foam. The merman did not reply, but went to the task of refilling his bathtub with water.

“Katara?” A knock at the door. Katara freezes, and the merman throws his head up, turning into a tense, cornered animal. Katara throws him a look. They both know what discovery will end in.

“Yes, Gran Gran?” Forced casual.

“Why is your blanket stuffed into the hamper?”

“Oh, uh...” Katara’s mind reeled to recollect her planned excuse. “I went walking yesterday, and got my feet wet in the shallow areas, and when I got back I just fell onto my bed and then they were wet and salty so I thought they should be washed.”

There was silence outside the door. Then, “Are you taking a bath?”

“...yes!”

“Alright, dear. I was thinking about heading to the store for some eggs, among other things... you teenagers eat so much! Will you be okay on your own?” Katara could almost see her Gran Gran’s smile at the question.

“Of course, Gran Gran! Am I not your smart and careful granddaughter?”

“That you are, dear. That you are.” Steps shuffle down the stairs. “I’ll be back in an hour! Don’t invite any boys while I’m gone!” Gran Gran called cheerfully before she left.

“Hah,” Katara mutters to herself, darkly. “If only you knew, Gran Gran.”


	4. Entertainment

**Summary for the Chapter:**

> She finally gets his name, and mermaids are skeptical about video games.

**Notes for the Chapter:**

> pure self-indulgence

“I’m bored,” complains the merman after Katara returns from her speed-shower in the downstairs bathroom. He rocks back and forth in his little pool. He feels confined.

“Unsurprising,” Katara retorts, teasing her hair back into the French braid. “You’re a fish out of water, and can’t go swimming around with the whales and sharks and sea-turtles, or go attacking boats and summoning storms with all your merman friends.”

His burning gaze turns on her. She holds fast. “We don’t summon storms,” he rumbles.

“Oh?” Katara raises an eyebrow. “I suppose you don’t eat babies, or that your women-folk don’t lure men to their deaths, either.”

“Not all of them,” is his dry response. “But none of us eat human babies. That would be disgusting.”

“Well, what do you eat, then?”

“Fish, seaweed, shark-eggs, snails, seagulls... whatever we catch,” is the slightly unsettling response. “What about humans?”

“Lately, humans have been learning to eat things that probably can’t even be classified as food... we’re supposed to eat fruits and vegetables, a bit of meat here and there, grains, fish... everything, basically.”

The merman grunts.

“Hey, what is your name?” Katara scoots forward on the toilet seat. “What should I call you, other than Mr. Merman?”

“Zuko,” he replies sullenly, resting his head on his crossed arms. The anger is slowly leaving him, Katara notices. She rather likes that.

“Zuko,” she tries. He raises an eyebrow. His only eyebrow. “What happened to your face?” she asks.

The reaction was rather dramatic. His fins all splay into their full glory, his gills flare out red and startling against his pale skin,  he bares his teeth at her and tries to back away, but doesn’t get far on account of being stuck in a bathtub. “None of your business,” he hisses.

“Okay, okay! Sorry.” She makes _calm down_ motions with her hands. “I didn’t know you were so sensitive about it,” she defends herself. “Do you have any family?” Changing the subject.

Zuko is silent for a while. “I have an Uncle,” he replies, quietly, “that I really should treat better.” Katara waits. “He’s probably the only one who’s ever taken care of me, other than my mother. But she’s gone.” The last part is so full of bitterness and anguish that Katara’s own heart squeezes.

“Me too,” she admits. “She’s dead.” Their eyes meet and they both feel connected, briefly, by their shared pain.

In order to shift the subject to more pleasant things, Katara ended up amusing him by introducing him to videogames. Her brother’s old Gameboy Advance SP, left behind once he’d moved on to shinier, sleeker consoles, was the perfect way to entertain the skeptical merman. She linked it with her own and put in a Kirby game.

“Am I the pink one, or the red one?” he kept asking.

“The pink one.”

“I want to be the red one.”

“You can’t right now.”

“What is the point of this game?”

“To beat all the enemies and win.”

“Why do I keep dying?” He was starting to get frustrated.

Katara bends over to watch his progress. “You have to jump over the holes in the ground,” she advises.

“Which one are you?”

“ _I’m_ the red one.”

“I wanted to be the red one.”

“Just focus on winning.”

The door opens downstairs, and Katara jumps up from the toilet seat. Zuko looks up at her, startled. “Are you leaving?” he asks.

“I’ll have to, or else Gran Gran will get suspicious.”

“But I want to keep playing.”

“You can.” She removes the link cable and starts the game for him. “Don’t get too loud,” she warns.

“No problem,” he mutters, leaning back into the tub.

“And don’t get it wet, or it’ll stop working.”

Zuko merely shoos her away with his hand.

Katara leaves the bathroom, making sure to close the door. Full of a strange, nervous energy, she skitters down the stairs. “Gran Gran! You’re back!” she yells.

“Any boys?” her grandmother asks, a mischievous grin on her old, wrinkled face. Katara hugs her, grabbing the grocery bags.

“Of course not!”


	5. Bittersweet

**Summary for the Chapter:**

> Everything comes to an end.

**Notes for the Chapter:**

> i really need to do some research on the anatomy and physiology of mermaids like jfc how do they work tbh

The days passed. In between outings to museums, art exhibitions, the zoo, and concerts with her beloved Gran Gran, Katara spent as much of her free time in the bathroom, keeping the merman quiet, whispered company. She kept him fed with the leftovers she took with her from restaurants, with canned fish from the pantry, anything she could get her hands on. Noticing the disappearance of these food items, Gran Gran merely smiled and attributed it to a growth spurt.

Zuko learned to refresh his water supply when the two women were gone, remaining silent as seaweed whenever he heard them return. He became proficient at the video games Katara proffered. But his mounting irritation at captivity and the long hours spent alone darkened his mood and made him snappish. The only way to get him out of these brooding moods were to surprise him with facts about human life, which Katara relished teaching him.

Her weeks of vacation with her grandmother were drawing to a close, and Zuko’s tail was slowly healing, despite his pessimistic comments about it. There were, of course, a few hiccups along the way; Katara entered the bathroom to find it awash in a sea of rosy bubbles, an upset and perplexed merman holding the remains of her Lush Comforter Bubble Bar. Her Gran Gran mentioned Katara’s incessant need to go to the bathroom and stay in there for inordinate amounts of time, and Katara quickly explained that she was, _y’know, at that time of the month._ Which of course led to an awkward explanation of periods for Zuko.

“You mean all human girls bleed from there for a week? And they don’t die?” he asked, fascinated and horrified at the same time. Katara was struck by the fact that he wasn’t awkward about it at all. Sokka frequently declared that he was _literally dying_ whenever he heard anyone mention periods. “They don’t get attacked by any land-hunters, or anything?”

“Well, I haven’t, at least...” she confessed, shifting her shoulders.

He looked at her, strangely. “You must be very fierce if the land-hunters leave you alone when you’re giving off the smell of fresh blood.” Katara was strangely pleased that he thought her so respected, so feared. Then she grew nervous that he might himself be able to scent it.

Zuko continued, his tail tilting slowly left to right. “If our women did that, they’d have sharks following them everywhere.” Katara had to admit that that was a very likely scenario.

With the passing of the days, Zuko became more and more frustrated with his captivity and thus more interested in the human world to try and pass the time. Katara returned his interest with equal fervor, peppering him with questions about his people.

“How do you, y’know, make merbabies?” she had asked, coloring slightly. The merman had stared at her face in fascination at this phenomenon for a while before she explained, “ _Embarrassment makes blood rush to the face in humans.”_

“Well,” he started, his fins fanning open and closed. “When a mommy and a daddy naiad love each other very much...”

Katara had gotten huffy at him, and he had smiled for the first time. The small curve filled her with pride.

Zuko’s interest in human legs increased exponentially after Katara started to ask him what it was like to swim with a tail and have fins and scales and such. Katara jumped and bent her knees and stood on one leg for him, which he watched with the kind of brooding concentration characterized by a furrowed brow and hunched shoulders. She was wiggling her toes at him from her seat on the toilet lid when he reached out an arm and took her foot in his hand.

The human girl stiffened, the merman taking no notice. He frowned and pressed his fingers into the pad of her foot, and Katara shrieked with laughter and fell off the toilet. Zuko froze, shocked, and Gran Gran immediately made her worry known.

“Katara?! Are you alright?” Her footsteps started up the stairs. Katara threw a panicked glance at the stunned face of the merman before barreling out of the bathroom, through the hallway, and onto her bed, where she quickly flicked her phone on.

“Yeah, Gran Gran!” she replied cheerfully. The footsteps faltered, but continued up the stairs.

Gran Gran entered her granddaughter’s room to find the girl sitting cross-legged on the bed, phone in hand and an innocently mirthful look on her face. The old woman’s worry softened into warm love. “Good news?” she asked.

“The best,” Katara replied. “Suki beat Sokka at basketball again.”

It twisted her heart to have to resort to such secrecy, but Zuko’s life was important. Important enough to look her grandmother in the face and lie; but the lie hung in her heart and poisoned it, contaminated all her thoughts until she couldn’t stand it.

“Gran Gran?” Katara asked later, after they had returned home from dinner at a local Thai restaurant. “Did you ever meet someone that you at first thought was... different, and didn’t belong? And who in the end turned out to be okay?”

The wine glass clinked onto the table. With a searching look at her granddaughter, Gran Gran straightened in her chair. She knew Katara was alluding to something; the child had been acting strangely for a while now, expressing a new need for privacy. ‘She’s becoming a woman,’ was her bittersweet realization.

“Katara. Do you remember what I told you of a certain Pakku?” Katara nodded in recognition and prepared herself for story-time. “Ah, Pakku. He was certainly devoted to me when I was around your age... he loved me for my looks, which were as stunning as yours are, my dear.” A smile rose to Katara’s face, vanished. “I didn’t like him very much, mainly because he was a chauvinistic moron and proud of it. I always liked to think I ran away from him when I left the city for a small town near the sea and married your grandfather. I met him again a few years ago... and I decided he may not be so bad after all.” She lifted her glass to her lips again to hide her smile, but Katara noticed and stored the information away for future analysis.

Later, secretly, before she went to sleep, Katara visited her merman again. He was sulking, turned away from her. For the first time she noticed the tiny, barely-there scales that ran up his spine and blurred into skin in between his shoulder blades.

“Zuko...?” she asks, perching on the toilet.

“What is it?” Darkly, from murky, angry depths.

“How am I going to get you back home?”

His fins flare, he turns around. There is a wildness in his eyes, a hunger for the place where he belongs, a need for saltwater and whalesong. His throat works. “The same way you got me here,” is his reply. His voice catches as it rises out of his chest.

Zuko looks at Katara and sees her upturned eyebrows, her lips pressed into a hard line. Something twists in his heart. He has grown to like this human, with her strange brown skin and ocean eyes.

Katara looks at Zuko and sees his single eyebrow, his dull red scar, the wet black hair that falls in slick strands over his forehead. Her heart gives a long-suffering squeeze. Her secret almost-friendship with this merman will be something she will never forget, she’s sure.

“I have to leave in three days,” she whispers, and the whisper is pain.

Zuko flips his tail and regards his tail fins. The black hatches holding the scraps together have done their job. He runs his fingers over them; the skin is tender and thin, but holds. “I will be able to swim again soon,” he mumbles.

“We’ll have to take the stitches out before you... go.” Katara regards her handiwork unhappily. The threads glisten with water.

The fins swish back and forth. Zuko speaks. “Tomorrow. So the holes can heal before.”

“Wouldn’t want sharks nibbling on it. Not after all my hard work.”

“Hah. Call that hard work? The stitches aren’t even _even,”_ he shoots back, a small, teasing lilt to his tone. Katara’s smile is a grimace, and his forehead is still furrowed.

The mood darkens as they contemplate the future.


	6. Promises

**Summary for the Chapter:**

> Farewells are said, but hope holds.

**Notes for the Chapter:**

> I'm gonna fucking cry

The shadows have melted from their daytime homes, covering the walls and floors of the house in intangible pools of ink. A path of towels leads the way down the stairs and out of the house. The sandy path leading to the beach is divided by a thick depression from the wheelbarrow. Occasional wet patches dot the string of heavy footsteps heading towards the ocean.

A girl-shadow sits in the sand, arm reaching up to hold the lip of the wheelbarrow as if afraid of it vanishing lest she let go. A spiked fin and sleek head stick out of the wheelbarrow. There is reluctant silence save for the rush of the waves.

“Hey. You never told me how you ended up here, on this beach.” She hugs her knees, the wind lifting the ends of her curls and spraying sand over her toes.

“It’s a long story,” responds the merman. His voice is husky with starlight and salt wind.

“You could at least tell me,” she mutters. “After all I’ve done for you.”

Zuko turns to look at his rescuer, the human girl who dragged him from the ocean to her own home. Took care of him, fed him, patched his broken tail, taught him. All he had ever expected from humans was violence, death, suffering, and a lack of fish to eat. And then this girl turns up in his life and he doesn’t know what to think anymore.

“What you did was truly honorable,” he murmurs, grudging admiration in his eyes. Katara’s heart flutters on the wind. “Any other human would have left me to die or finished me off. You are strange, but honorable.”

“Thank you.” She feels touched by something large and incomprehensible.

“I’d give you something to prove my gratitude,” he begins, looking back out towards the water. “But I have nothing.”

Katara wonders if he means this in relation to simple possessions or in a more terrible, general sense.

“So all I can give you are my thanks and a wish.”

Katara brightens considerably. “Merpeople can grant wishes? You never told me that!”

A smirk. “We can’t grant wishes. But we can try.” He leans out of the wheelbarrow.

“Do you think people and naiads will ever stop hating each other?” Katara asks, hopefully.

His face grows serious. “We can only hope that we don’t. Humans and naiads don’t mix.”

“But I can tell them about you, I can convince them that you’re not all bad...”

Zuko laughs. The sound is hollow and hopeless. “Humans will never stop hurting the ocean, the sea creatures, our home and food supply. And so we will never stop fighting back.” The girl’s heart dims, before brightening into a hard-edged shard of brave, brilliant ice.

“Then my wish is to see you again.” She watches as his eyes darken.

“That’s a bad idea,” he warns.

“I don’t care,” she gives back, passion starting to catch in her blood. “I saved your life. I should at least be able to check whether it was worth the trouble.”

He regards her, thinking. His tail fin, peppered in tiny holes where the threads were pulled, sways from side to side. Then his hand releases the edge of the wheelbarrow and clasps around her forearm.

Katara, startled, mimics him. His skin is wet and feverish under her wrist.

“I swear on my honor that we will speak again,” he intones, his voice strong with conviction.

The following events unfold in a dazed blur. Katara pushes the wheelbarrow into the waves. Soft and gentle they are, folding lovingly around her feet, the sand sucking out from underneath them when the water returns to the sea. Zuko stares intently out over the water, rigid with excitement. Then she tilts the wheelbarrow and he slides down and is swallowed by the surf.

Katara feels something well up in her eyes, and briefly reflects on the absurdity of a girl with a capsized wheelbarrow alone on the beach at night. In between owlish blinks she scans the dark waves, searching. There. A fin? For a moment a spiky crest surfaces, moving steadily away from land. It disappears, and a dark head pushes up through the water. Moonlight reflects off of golden eyes, and she holds them in her gaze for as long as she can.

And then her merman dips his head.

He’s gone.


End file.
